Effect of repeated endoscopic screening on the incidence and treatment of gastric cancer in health screenees

National Statistics of Endoscopic Submucosal Dissection for Early Gastric Cancer in Korea

PURPOSE

Endoscopic submucosal dissection (ESD) is the standard treatment for early gastric cancer (EGC) with a low risk of lymph node metastasis. In Korea, ESD was included in the National Health Insurance (NHI) coverage in 2011, which was expanded in 2018. In the present study, we investigated the status and trends of ESD for EGC over the past decade since its incorporation into the NHI system.

MATERIALS AND METHODS

We analyzed the data from the National Health Insurance Service (NHIS) database from 2011 to 2021, focusing on patient characteristics, number of ESD procedures, in-hospital length of stay (LOS), and total medical cost (TMC) per admission. In addition, we conducted an interrupted time series analysis to assess the impact of changes in insurance coverage on these variables.

RESULTS

Overall, 95,348 cases of ESD for EGC were identified. A consistent annual increase in ESD procedures was observed, particularly in tertiary care hospitals and among patients aged >60 years. The overall median LOS and TMC were 4 days and 2,123,000 KRW, respectively. The 2018 insurance coverage expansion did not significantly affect the number of ESD procedures or LOS; however, the TMC increased significantly.

CONCLUSIONS

Our study illustrates decade-long trends in the ESD for EGC in Korea. The policy needs to be revised continuously to optimize ESD use and improve resource allocation within healthcare systems.

The optimal interval of surveillance gastroscopy after endoscopic resection for gastric neoplasia: a multicenter cohort study

BACKGROUND/AIMS

Due to the possible metachronous recurrence of gastric neoplasia, surveillance gastroscopy is mandatory after endoscopic resection for gastric neoplasia. However, there is no consensus on the surveillance gastroscopy interval. This study aimed to find an optimal interval of surveillance gastroscopy and to investigate the risk factors for metachronous gastric neoplasia.

METHODS

Medical records were reviewed retrospectively in patients who underwent endoscopic resection for gastric neoplasia in 3 teaching hospitals from June 2012 to July 2022. Patients were divided into two groups; annual surveillance vs. biannual surveillance. The incidence of metachronous gastric neoplasia was identified, and the risk factors for metachronous gastric neoplasia were investigated.

RESULTS

Among the 1,533 patients who underwent endoscopic resection for gastric neoplasia, 677 patients were enrolled in this study (annual surveillance 302, biannual surveillance 375). Metachronous gastric neoplasia was observed in 61 patients (annual surveillance 26/302, biannual surveillance 32/375, P = 0.989), and metachronous gastric adenocarcinoma was observed in 26 patients (annual surveillance 13/302, biannual surveillance 13/375, P = 0.582). All the lesions were removed by endoscopic resection successfully. In a multivariate analysis, severe atrophic gastritis on gastroscopy was an independent risk factor for metachronous gastric adenocarcinoma (odds ratio 3.8, 95% confidence interval 1.4‒10.1; P = 0.008).

CONCLUSIONS

Meticulous observation to detect the metachronous gastric neoplasia is necessary for patients with severe atrophic gastritis during follow-up gastroscopy after endoscopic resection for gastric neoplasia. Annual surveillance gastroscopy might be enough after endoscopic resection for gastric neoplasia.

Gastric cancer clinical characteristics and their altered trends in South China: An epidemiological study with 2,800 cases spanning 26 years

BACKGROUND

Gastric cancer (GC) is a serious threat to human health. The clinical GC characteristics in China may be impacted by changes in people's lifestyles and the promotion of early GC (EGC) screening. The present study aims to evaluate the recent trends of GC characteristics in South China and search for hazardous factors limiting the survival time of GC patients.

METHODS

Data on GC patients that were hospitalized in the Department of Digestive Center, the First Affiliated Hospital, Sun Yat-sen University, from 1994 to 2019 were collected and divided into two categories according to the time when the EGC screening began in China: the PRE group (previous 13 years, 1994-2006) and the PAS group (past 13 years, 2007-2019).

RESULTS

We found that, although the 5-year survival rate increased in the PAS group compared with the PRE group (P < 0.0001), patients with age ≥60 years or Borrmann type IV still had a worse prognosis. In the PAS group, the larger percentages of elderly patients and patients with Borrmann type IV in the lymphatic metastases (N1) group (41.0% vs. 51.1%, P = 0.0014) and stage IV subgroup (20.7% vs. 32.2%, P = 0.016), respectively, when compared with the PRE group, may have contributed to the poor outcome of GC. By comparing the odds ratio (OR) of 5-year overall survival (OS) in the two 13-year periods, female sex and T2 turned into risk factors because of a greater proportion of Borrmann type IV or elderly patients in the PAS group (OR = 0.983, 95% CI = 0.723-1.336 vs. OR = 1.277, 95% CI = 1.028-1.586 and OR = 1.545, 95% CI = 0.499-4.775 vs. OR = 2.227, 95% CI = 1.124-4.271, respectively).

CONCLUSIONS

Despite the GC epidemiology changes, the overall prognosis of GC patients has improved in South China. However, old age and Borrmann type IV are still the major restrictions affecting the survival of GC patients, a situation which calls for additional attention.

Clinicopathological features and prognosis of gastric tube cancer after esophagectomy for esophageal cancer: a nationwide study in Japan

BACKGROUND

Survivors of esophageal cancer post-esophagectomy may sometimes develop gastric tube cancer (GTC). However, its clinical characteristics have not been elucidated. We conducted a retrospective nationwide survey of GTCs to clarify them.

METHODS

A questionnaire on GTCs was sent by e-mail and mail to 116 institutions certified by the Japan Esophageal Society. A total of 608 GTC cases diagnosed and treated between 2001 and 2015 were registered from 62 institutions.

RESULTS

The median age at diagnosis was 71 years, with 88.9% being diagnosed with stage I. Sixty percent of GTC cases were in the anal third of the gastric tube and 79.7% were differentiated adenocarcinomas. The median interval between esophagectomy and GTC diagnosis was 6 years, with approximately 25% of patients being diagnosed more than 10 years later. The 5-year overall survivals (5-OSs) after endoscopic and surgical treatments for GTC were 75.9% and 52.7%, respectively. Patients whose GTC was diagnosed without symptoms or by regular follow-up examination showed better 5-OSs compared to others (69.7% vs. 41.2%, p < 0.0001; and 71.4% vs. 41.8%, p < 0.0001, respectively). The prognosis of GTC cases diagnosed within 2 years of the preceding upper gastrointestinal endoscopy (UGI) was better than that in cases diagnosed longer than 2 years (5-OS: 73.4% vs. 48.8%, p < 0.05).

CONCLUSION

This nationwide survey revealed the clinicopathological features of GTCs for the first time. Early detection is important in improving the prognosis of GTC, and it is recommended that UGI endoscopy be continued every 2 years for 10 or more years after esophagectomy.

Effect of gastric cancer screening on long-term survival of gastric cancer patients: results of Korean national cancer screening program

BACKGROUND

Gastric cancer (GC) is the most common cancer type in Korea. Korean National Cancer Screening Program (KNCSP) offer either upper gastrointestinal series (UGIS) or upper endoscopy biennially for adults aged ≥ 40. This study aimed to investigate the effect of cancer screening program on the long-term survival among GC patients.

METHODS

A nationwide population-based cohort was constructed based on three national databases. Overall, 46,701 GC patients diagnosed in 2008 and 2009 were included in our final analysis, and they were followed-up until the end of 2019. Survival curves were estimated using the Kaplan-Meier analysis with the log-rank test. Cox proportional-hazards regression analysis was used to report the hazard ratios (HRs) with 95% confidence intervals.

RESULTS

A total of 18,614/46,701 (39.9%) patients died during the median follow-up time of 10.5 years. The survival rate was higher among screened patients (65.8%) than never-screened patients (49.1%). Screened patients had 53% (HR, 0.47; 95% CI 0.45-0.48) lower risk of death from GC. The HRs of GC-specific mortality was lower in upper endoscopy group (HR = 0.36; 95% CI = 0.34-0.37) compared with UGIS (HR = 0.69; 95% CI = 0.67-0.73). Screened patients within 2 years prior to cancer diagnosis had a 35% reduction in risk of GC death. The figure decline to approximately 19% among patients with interval time since last screening of > 3 years.

CONCLUSIONS

Our findings emphasized the positive effects of GC screening on long-term GC patient survival. Also, patients screened by upper endoscopy or within 2 years before diagnosis had the best survival outcomes.

Current status of the gastric cancer screening program in Korea

Background: In 2019, gastric cancer was one of the most common cancers in Korea. As a secondary prevention strategy for gastric cancer, the cancer screening has been provided since 1999 by the National Cancer Screening Program every 2 years for adults aged ≥40 years.Current Concepts: The participation rates for gastric cancer screening program have increased from 7.4% in 2002 to 62.9% in 2019. Until 2017, either upper gastrointestinal series or endoscopy were recommended for screening method. Since 2018, endoscopy has become the preferred screening method and 89.1% of the participants underwent endoscopy in 2019. After the introduction of the screening program, the 5-year relative survival rates have markedly improved (43.9% between 1993 and 1995 vs. 77.5% between 2015 and 2019), and the proportion of early gastric cancer detection has increased (28.6% in 1995 vs. 63.6% in 2019). The risk of death from gastric cancer decreased by 47% in participants who had undergone endoscopy screening. Additionally, the gastric cancer screening program is cost-effective, and endoscopy-associated adverse events rarely occur.Discussion and Conclusion: With the implementation of the screening program, mortality due to gastric cancer has decreased owing to early detection. After the completion of ongoing clinical trials in the general population, the primary prevention strategy of Helicobacter pylori eradication should be considered to effectively reduce the incidence of gastric cancer. Further studies are also required to provide optimal screening interval according to the presence of risk factors including H. pylori infection and presence of gastric mucosal atrophy.

Current Evidence for a Paradigm Shift in Gastric Cancer Prevention From Endoscopic Screening to Helicobacter pylori Eradication in Korea

Gastric cancer is prevalent in Korea and ranked as the third most common cancer in 2019, followed by lung and thyroid cancers. The National Cancer Screening Program (NCSP) for gastric cancer has been implemented in adults aged ≥40 since 1999 and involves endoscopic screening every 2 years. The beneficial effects of the current NCSP on early cancer detection, cost-effectiveness, and mortality reduction are evident. However, the screening program results in a large socioeconomic burden and the consumption of medical resources, as it focuses solely on secondary prevention (early detection) rather than primary prevention of cancer. Helicobacter pylori is defined as a group I carcinogen by the International Agency for Research on Cancer. Hence, its eradication has been suggested as an important primary gastric cancer prevention strategy. Well-designed randomized controlled trials involving high-risk groups (post-endoscopic resection of early gastric cancer and family history of gastric cancer) and long-term follow-up studies in the general population have provided high-quality evidence regarding the effects of H. pylori eradication on gastric cancer prevention. In this review, we discussed the evidences for a possible modification of the current gastric cancer secondary prevention strategy by introducing primary prevention through H. pylori eradication. Areas for future research to optimize primary prevention strategies were also suggested.

Association of Regular Endoscopic Screening with Interval Gastric Cancer Incidence in the National Cancer Screening Program

Although regular endoscopic screening may help in early detection of gastric cancer, interval cancer remains a problem in the screening program. This study evaluated the association between regular endoscopic screening and interval cancer detection in the Korean National Cancer Screening Program (KNCSP). We defined three groups (regularly, irregularly, and not screened) according to the screening interval, and the trends in the interval cancer rate (ICR) between the groups were tested using the Cochran-Armitage test. The influence of regular endoscopic screening on the risk of interval cancer was evaluated using multivariable logistic regression. Among the 11,642,410 participants who underwent endoscopy, the overall ICR was 0.36 per 1000 negative screenings. The ICR of the not screened group (0.41) was the highest among the three groups and the risk of interval cancer in this group was 1.68 times higher (p < 0.001) than that in the regularly screened group. Women in their 40s who had regular screening with no history of intestinal metaplasia and gastric polyps would have the lowest probability of having interval cancer (0.005%). Regular participation in endoscopic screening programs for reducing the risk of interval cancer may help to improve the quality of screening programs.

A nomogram to predict risk of lymph node metastasis in early gastric cancer

Lymph node (LN) metastasis is known as one of the most important prognostic factors for early gastric cancer (EGC) patients. Patients without LNM normally have better prognosis. However, there is no evaluation criteria to accurately assess the possibility of LN metastasis. Therefore, this study aims to establish an effective nomogram for prognosis prediction. In this study, 285 EGC patients from January 2010 to December 2015 were enrolled. Pearson's Chi-Square (χ2) test (including continuity correction when appropriate) and logistics regression analyses was used to identify the risk factors for LN metastasis. The independent risk factors identified were then incorporated in a nomogram model. The predictive accuracy and discriminative ability of the nomogram were evaluated by receiver operating characteristic curve (ROC) and calibration curve. LN metastasis occurred in 59 (20.7%) EGC patients. And most of these patients were submucosal cancers (48/59). Chi-square test indicated lymphovascular emboli, carbohydrate antigen 19-9 (CA19-9), ulcer, tumor size, tumor infiltration and histological grade were the risk factors, and multivariate logistics analyses confirmed all these six factors were independent risk factors of LN metastasis, which were selected to construct the nomogram. The nomogram proved well calibrated and had good discriminative ability (C-index value: 0.842). The proposed nomogram could result in more-accurate risk prediction for EGC patients.

Gastric cancer: lessons learned from high-incidence geographic regions

Gastric cancer is a global health concern. There is a marked geographical variability in the incidence of gastric cancer, with higher incidence in East and Central Asia followed by Latin America and Eastern Europe. Survival rates in gastric cancer are low and strongly stage dependent. Due to the limited survival benefit achieved from currently available therapeutic options, prevention and early diagnosis are essential to minimize morbidity and mortality from this disease. Countries with high incidence of gastric cancer have pioneered the development and implementation of prevention and screening programs. Helicobacter pylori (H. pylori) eradication and dietary modifications are the main preventive strategies. Upper gastrointestinal (UGI) endoscopy is the mainstay screening strategy for early diagnosis. In this article, we review the lessons learned for gastric cancer diagnosis and treatment from high-incidence areas and discuss their applicability for treatment in the Western world to reduce morbidity and mortality from this disease.

Effectiveness of oral phloroglucinol as a premedication for unsedated esophagogastroduodenoscopy: A prospective, double-blinded, placebo-controlled, randomized trial

Background

Anti-spasmodic agents are commonly injected during esophagogastroduodenoscopy (EGD) to improve visualization of the gastric mucosa by inhibiting gastrointestinal (GI) peristalsis. The availability of oral anti-spasmodic agents would increase convenience. In this study, we evaluated the effectiveness of oral phloroglucinol (Flospan^®) as a premedication for unsedated EGD.

Methods

A prospective, double-blinded, placebo-controlled, randomized controlled trial was conducted in a tertiary hospital. Individuals scheduled to undergo unsedated EGD were randomly assigned to receive either oral phloroglucinol or matching placebo 15 min before EGD. The primary outcome was the rate of complete gastric peristalsis suppression. Outcomes were assessed by independent investigators according to the classification of gastric peristalsis and ease of intragastric observation at the beginning (Period A) and end (Period B) of EGD.

Results

Overall, 71 phloroglucinol-treated and 71 placebo-treated participants (n = 142 total) were included. The phloroglucinol group showed significantly higher proportions of participants with complete gastric peristalsis suppression than the placebo group (22.5% vs. 9.9%, P = 0.040). The ease of intragastric observation was significantly better in the phloroglucinol group than in the placebo group at Periods A (P < 0.001) and B (P = 0.005). Patients in both groups had comparable adverse events and showed willingness to take the premedication at their next examination.

Conclusions

Oral phloroglucinol significantly suppressed gastrointestinal peristalsis during unsedated EGD compared with placebo (Clinical trial registration number: NCT03342118).

Risk of Second Primary Malignancies among Patients with Early Gastric Cancer Exposed to Recurrent Computed Tomography Scans

Simple Summary

Cancer risk after radiation exposure during childhood has been extensively documented in the literature, although cancer risk associated with recurrent computed tomography (CT) scans during adulthood is less understood. We found a significant relationship between the frequency of CT scans and the subsequent incidence of secondary primary malignancies in patients who have undergone curative resection for early gastric cancer (EGC). On the basis of the low incidence of extragastric recurrence and the risk of radiation exposure, we suggest that overzealous CT surveillance should be avoided in adult patients with EGC.

Abstract

Although computed tomography (CT) scans are very useful for identification or surveillance of malignancy, they are also associated with the risk of cancer caused by ionizing radiation. We investigated the risk of second primary malignancies (SPMs) after frequent abdominopelvic CT scans in a cohort of Korean patients with early gastric cancer (EGC). We performed a cohort study of 11,072 patients who underwent resection for EGC at Samsung Medical Center and validated the results using data from 7908 patients in a Korean National Health Insurance Service cohort. Cox proportional hazards regression model was used to estimate hazard ratios (HRs) for intra-abdominal SPM. During 43,766.5 person-years of the follow-up at our center, 322 patients developed intra-abdominal SPMs. Patients who underwent receiving >8 abdominopelvic CT scans had a significantly greater risk of developing SPM (HR, 2.73; 95% CI, 1.66–4.50; p < 0.001) than those who had with ≤8 scans. For each additional abdominopelvic CT scan, the adjusted HR for SPM was 1.09 (95% confidence interval (CI), 1.03–1.14). Similar results were observed in the Korean National Health Insurance Service cohort (adjusted HR, 1.14; 95% CI, 1.07–1.22). Significantly elevated risk of SPM was still observed when considering a 2-year latency period (adjusted HR, 2.43; 95% CI, 1.37–4.48) and a 3-year latency period (adjusted HR, 2.17; 95% CI, 1.06–4.47). Frequent abdominopelvic CT scans are associated with an elevated risk of SPMs after the treatment of EGC. Thus, physicians need to weigh carefully the clinical benefits of CT examinations against the potential risks of radiation exposure.

Characteristics of interval gastric neoplasms detected within two years after negative screening endoscopy among Koreans

Background

In Korea, where gastric cancer is highly prevalent, biennial endoscopy is recommended among individuals over 40. Even under regular screening, some are still diagnosed at advanced stages. We aimed to identify characteristics of interval gastric neoplasms (IGNs) with rapid progression.

Results

Newly-diagnosed gastric neoplasms detected in screening endoscopy between January 2004 and May 2016 were reviewed. Among them, those who had previous endoscopy within 2 years were enrolled. Endoscopic findings, family history of gastric cancer, smoking, and H. pylori status were analysed. Totally, 297 IGN cases were enrolled. Among them, 246 were endoscopically treatable IGN (ET-IGN) and 51 were endoscopically untreatable IGNs (EUT-IGN) by the expanded criteria for endoscopic submucosal dissection. Among EUT-IGNs, 78% were undifferentiated cancers (40/51) and 33% showed submucosal invasion (13/40). They were median 2.0 cm in size and more commonly located in the proximal stomach than ET-IGNs (70.6% vs. 41.9%, p < 0.001). EUT-IGN was independently related with age < 60 (OR, 2.09; 95%CI, 1.03–4.26, p = 0.042), H. pylori (OR, 2.81; 95%CI, 1.20–6.63, p = 0.018), and absent/mild gastric atrophy (OR, 2.67; 95%CI, 1.25–5.72, p = 0.011). Overall and disease-specific survival were not significantly different between the two groups, however EUT-IGN tended to have short disease-specific survival (overall survival, p = 0.143; disease-specific survival, p = 0.083).

Conclusions

Uniform screening endoscopy with two-year interval seems not enough for rapid-growing gastric neoplasms, such as undifferentiated cancers. They tended to develop in adults younger than 60 with H. pylori infection without severe gastric atrophy. More meticulous screening, especially for proximal lesions is warranted for adults younger than 60 with H. pylori infection before development of gastric atrophy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-07929-y.

Antibody-Targeted Imaging of Gastric Cancer

The specificity of antibodies for antigens overexpressed or uniquely expressed in tumor cells makes them ideal candidates in the development of bioconjugates for tumor imaging. Molecular imaging can aid clinicians in the diagnosis of gastric tumors and in selecting patients for therapies targeting receptors with a heterogeneous intratumoral or intertumoral expression. Antibodies labeled with an imaging radiometal can be used to detect primary tumors and metastases using whole-body positron emission tomography (PET) or single photon emission computed tomography (SPECT), both during diagnosis and monitoring disease response. Conjugated with fluorescent dyes, antibodies can image tumors by targeted optical imaging. This review provides an overview of the most recent advances in the use of antibodies labeled with radiometals or conjugated with fluorescent dyes for gastric cancer imaging.

HER2 as a potential biomarker of lymph node metastasis in undifferentiated early gastric cancer

Human epidermal growth factor receptor 2 (HER2) is implicated in several cancers, including gastric cancer. However, limited data are available regarding its clinical significance in early gastric cancer (EGC). We evaluated the clinical significance of HER2 overexpression in patients with EGC. We retrospectively reviewed 727 patients who underwent surgical treatment for EGC between October 2010 and August 2017. HER2 expression was analysed in 680 EGC cases by immunohistochemistry and classified as negative (0 and 1+), equivocal (2+), or positive [overexpression (3+)]. Among patients with differentiated EGC, the number of patients with HER2 overexpression was not significantly different from that of HER2-negative patients in terms of age, sex, tumour size, location, gross type, depth of invasion, presence of lymphovascular invasion (LVI), and presence of lymph node metastasis (LNM). However, in patients with undifferentiated EGC, HER2 overexpression was significantly correlated with LVI and presence of LNM compared with HER2-negative patients. Multivariate analysis indicated HER2 overexpression as a good predictive marker of LNM in patients with undifferentiated EGC. HER2 expression is associated with LNM in undifferentiated EGC. Therefore, the importance of HER2 overexpression in EGC should not be overlooked, and further studies are needed to identify its clinical significance.

Family History of Gastric Cancer and Helicobacter pylori Treatment

BACKGROUND

Helicobacter pylori infection and a family history of gastric cancer are the main risk factors for gastric cancer. Whether treatment to eradicate H. pylori can reduce the risk of gastric cancer in persons with a family history of gastric cancer in first-degree relatives is unknown.

METHODS

In this single-center, double-blind, placebo-controlled trial, we screened 3100 first-degree relatives of patients with gastric cancer. We randomly assigned 1838 participants with H. pylori infection to receive either eradication therapy (lansoprazole [30 mg], amoxicillin [1000 mg], and clarithromycin [500 mg], each taken twice daily for 7 days) or placebo. The primary outcome was development of gastric cancer. A prespecified secondary outcome was development of gastric cancer according to H. pylori eradication status, assessed during the follow-up period.

RESULTS

A total of 1676 participants were included in the modified intention-to-treat population for the analysis of the primary outcome (832 in the treatment group and 844 in the placebo group). During a median follow-up of 9.2 years, gastric cancer developed in 10 participants (1.2%) in the treatment group and in 23 (2.7%) in the placebo group (hazard ratio, 0.45; 95% confidence interval [CI], 0.21 to 0.94; P = 0.03 by log-rank test). Among the 10 participants in the treatment group in whom gastric cancer developed, 5 (50.0%) had persistent H. pylori infection. Gastric cancer developed in 0.8% of participants (5 of 608) in whom H. pylori infection was eradicated and in 2.9% of participants (28 of 979) who had persistent infection (hazard ratio, 0.27; 95% CI, 0.10 to 0.70). Adverse events were mild and were more common in the treatment group than in the placebo group (53.0% vs. 19.1%; P<0.001).

CONCLUSIONS

Among persons with H. pylori infection who had a family history of gastric cancer in first-degree relatives, H. pylori eradication treatment reduced the risk of gastric cancer. (Funded by the National Cancer Center, South Korea; ClinicalTrials.gov number, NCT01678027.).

Safety and effectiveness of endoscopic mucosal resection or endoscopic submucosal dissection for gastric neoplasia within 2 days' hospital stay

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have been well-established methods of treating upper gastrointestinal neoplasia. The aim of this study was to identify the safety and effectiveness of endoscopic treatment for gastric neoplasia within a 2-day hospital stay.Between 2004 and 2015, a total of 914 patients with gastric neoplasia were treated with EMR or ESD within 2 days of hospitalization. The neoplasia sites, en bloc resection rates, pathology, local residual neoplasia rates, and major complications were evaluated retrospectively.The mean age was 63.4 years old, and 636 (69.6%) patients were male. Adenoma was the most common final diagnosis (60.9%), followed by adenocarcinoma (28.9%). The first follow-up endoscopy was performed 4.9 ± 1.1 months after the procedure, and an average of 4.4 endoscopic examinations were performed for 7.16 years (range, 2.1 to 10.2 years). Additional surgery was performed in 11 (1.2%) cases based on post-procedure pathology results. On follow-up endoscopy, a mean of 5.9 months after the procedure, there were 18 residual neoplasia cases (EMR = 13, ESD = 5). Only 4 (0.4%) patients returned to the emergency unit with delayed bleeding, but all 4 cases were successfully controlled with endoscopic treatment. There were no other complications such as delayed perforation or aspiration pneumonia during the 2 days in hospital.EMR and ESD within only 2 days in hospital showed safe and effective outcomes in terms of managing early gastric neoplasia with low complication and local residual rates.

Gastric Cancer - From Aetiology to Management: Differences Between the East and the West

Gastric cancers are highly prevalent in both the East and the West, although they differ in aetiology and prognostic outcome. Management of gastric cancer from screening to definitive treatment varies substantially between Eastern and Western countries and regions, owing to numerous factors, including government incentives to carry out population-wide screening programmes to detect early disease, differences in clinical and biological tumour behaviours and responsiveness to treatment, patient accessibility to effective treatment, etc. This review highlights and contrasts the differences in tumour aetiology and histology, as well as the management approaches between the East and the West, which gives important insights and inspirations on future international multicentre research collaboration to combat this dreadful malignancy.

"Four-Step Procedure" of laparoscopic exploration for gastric cancer in West China Hospital: a retrospective observational analysis from a high-volume institution in China

BACKGROUND

The preoperative work-up has limitations on finding peritoneal dissemination (PD) in gastric cancer patients. Laparoscopic exploration (LE) can discover radiographically occult PD, obtain accurate stage and avert futile laparotomy. The aim of our study was to introduce "Four-Step Procedure" LE in West China Hospital and further evaluate its safety and feasibility.

METHODS

We conducted a retrospective analysis on 165 patients from July 2016 to December 2017 who underwent "Four-Step Procedure" LE in gastrointestinal surgery department of West China Hospital. All the patients were diagnosed with gastric adenocarcinoma without explicit distant metastasis through Computed Tomography and/or Gastrointestinal Ultrasonography. Peritoneal lavage cytological examination (CY) was routinely performed during LE in our research. The "Four-Step" technical process of LE was introduced comprehensively. The clinicopathologic features and the presence of PD or CY at LE were analyzed, and the stratified analysis by cT and cN stages on the proportion of P1 and/or CY1 was also reported in this study.

RESULTS

Total of 165 patients accepted LE in our study, among these patients: 27 (16.4%) patients with P1 and/or CY1: 19 (11.5%) patients were found PD (P1), 17 (10.3%) patients with positive cytological examination (CY1) and 9 (3.6%) patients with P1Cy1. The stratified analysis by cT stage indicated that there was no P1 and/or Cy1 in cT1-cT2 stages, 1 (2.7%) patient with P1 and 1 (2.7%) with Cy1 in cT3 stage, 18 (20.0%) patients with P1 and 16 (17.8%) with Cy1 in cT4 stage. After LE, there were 74 (44.8%) patients underwent laparoscopic assistant gastrectomy, 25 (15.2%) patients with open gastrectomy, 50 (30.3%) patients with neoadjuvant chemotherapy and 16 (9.7%) patients with palliative chemotherapy and/or conversion therapy.

CONCLUSION

"Four-Step Procedure" LE is reliable and feasible for gastric cancer. From our study, LE has unique superiority on ascertaining PD and cytological examination and LE should be recommended in cT4 stage gastric cancer before resection.

Three-year interval for endoscopic screening may reduce the mortality in patients with gastric cancer

BACKGROUND

Endoscopic screening has been adopted in South Korea for the national screening of gastric cancer (GC). This study aimed to assess the effect on overall survival of GC patients and determine the optimal endoscopic screening interval.

METHODS

The baseline characteristics and overall survival of GC patients treated at the National Cancer Center, Korea, between 2010 and 2016 were compared between those without a history of endoscopic evaluation (group N) and those in whom the interval between the last endoscopic evaluations and diagnosis of GC was ≤ 1, 1-2, 2-3, 3-4, or > 4 years (groups 1-5, respectively).

RESULTS

A total of 2362 patients met the criteria for the study (1060 in group N and 1302 in groups 1-5). More patients in groups 1-5 were diagnosed with stage I GC (83.7, 83.7, 71.8, 78.2, and 71.6%, respectively) than in group N (62.4%, P < 0.001) and were treated endoscopically (38.8, 33.8, 24.7, 21.8, and 15.5%, respectively, vs. 13.5%; P < 0.001). Group 2 had less-advanced tumor stages (P = 0.001) and was more likely to have received endoscopic treatments (P = 0.026) than group 3. Hazard ratios for death were significantly lower in groups 2 (0.45; 95% confidence interval [CI], 0.32-0.64) and 3 (0.57; 95% CI, 0.33-0.98) than in group N; the decrease was not significant in group 4 (0.49, 95% CI, 0.20-1.20).

CONCLUSIONS

Endoscopic screening every 3 years may reduce the mortality of GC patients, though screenings at least every 2 years may benefit patients with less-advanced stages.

Optimal Endoscopic Screening Interval for Early Detection of Gastric Cancer: a Single-Center Study

BACKGROUND

The optimal endoscopic screening interval for early gastric cancer (EGC) detection still remains controversial. Thus, we performed this prospective study to clarify the optimal interval between endoscopic examinations for EGC detection.

METHODS

A questionnaire survey for penultimate endoscopy and gastric cancer (GC) diagnosis interval was used; the findings were then analyzed. The patients were divided into two groups according to GC type and endoscopic examinations intervals.

RESULTS

A total of 843 patients were enrolled. The endoscopic GC detection interval (P < 0.001), tumor location (P < 0.001), tumor size (P < 0.001), histology (P < 0.001), tumor stage (P < 0.001), and treatment modality (P < 0.001) showed significant differences in the univariate analysis between EGC and advanced gastric cancer (AGC). Endoscopic examination intervals below 2 years and 3 years were associated with higher proportions of EGC detection (adjusted odds ratio, 2.458 and 3.022, respectively) (P < 0.001). The patients with endoscopic examination to GC diagnosis interval of < 2 years showed significant differences in tumor size (P < 0.001), tumor stage (P < 0.001), and treatment modality (P < 0.001) compared to those with intervals of > 2 years and without screening. Similar results were observed in those with < 3-year intervals.

CONCLUSION

Triennial endoscopic screening might be as effective as biennial screening in increasing the detection rate of EGC and the risk of subsequent curable endoscopic resections.

Factors Affecting Endoscopic Curative Resection of Gastric Cancer in the Population-Based Screening Era

Background/Aims

Since population-based screening for gastric cancer in Korea was implemented, endoscopic treatment of early gastric cancer has become increasingly popular. This study investigates factors affecting endoscopic curative resection of early gastric cancer in population-based screening for gastric cancer.

Methods

We retrospectively reviewed data of patients with newly diagnosed gastric cancer who underwent treatment at Seoul St. Mary’s Hospital. All patients completed questionnaires about clinical information, including interval between surveillance tests for gastric cancer.

Results

Of 469 gastric cancer patients, 147 (31.3%) had undergone curative endoscopic resection, 260 (55.4%) had undergone curative surgical resection, and 62 (13.3%) underwent non-curative resection or were in an inoperable state. Patients with curative endoscopic resection had fewer alarm symptoms/signs than other groups. In multivariate analysis, regular surveillance endoscopy was the only factor predicting curative endoscopic resection (odds ratio [OR], 6.099; 95% confidence interval [CI], 2.532–14.933). In addition, patients undergoing gastric cancer screening had a significantly higher rate of endoscopic curative resection compared with subjects who had never been screened. (1-year interval: OR, 49.969; 95% CI, 6.340–393.827, 2-year interval: OR, 15.283; 95% CI, 1.833–127.406, over 2-year interval: OR, 10.651; 95% CI, 1.248–90.871). Shorter screening test intervals were associated with higher rates of endoscopic curative resection.

Conclusions

Regular surveillance testing was the independent factor predicting curative endoscopic resection of gastric cancer.

A CD44-specific peptide, RP-1, exhibits capacities of assisting diagnosis and predicting prognosis of gastric cancer

Early diagnosis and evaluation of prognosis are both crucial for preventing poor prognosis of patients with gastric cancer (GC), a leading cause of cancer-related deaths worldwide. Cluster of differentiation 44 (CD44), an indicator of cancer stem cells, can be specifically targeted by molecular probes and detected in tissues of GC in a large quantity. In current study we found that RP-1, a specific peptide binding to CD44 protein, exhibited the potentials of specific binding to CD44 high-expressing cancer cells both in vitro and in vivo, and the capacity of predicting prognosis of human GC in a microarray assay. Results showed that RP-1 was characterized by high affinity, sensitivity and specificity, and low toxicity, suggesting RP-1 could be an ideal bio-probe for accessory diagnosis of GC. Further immunohistochemical studies and statistical analysis of tissue microarray of human GC demonstrated similar sensitivity and specificity of RP-1 with the monoclonal anti-CD44 antibody in the diagnosis of GC, and even proved that positive RP-1 could be an independent risk factor. Therefore, this study suggests RP-1 has the potentials of binding to CD44 protein expressed on the membrane of GC cells, and demonstrates the feasibility and reliability of its further application in molecular diagnosis and prognostic prediction of GC.

Natural history of gastric cancer from a retrospective review of endoscopic images of older patients with interval gastric cancer

AIM

Interval gastric cancers (IGC) are defined as those diagnosed after negative results of endoscopy carried out within the past 10 years. We aimed to investigate the characteristics of IGC and the natural history of gastric cancer (GC) from a retrospective view of endoscopic images of older patients with IGC.

METHODS

We retrospectively reviewed endoscopic images of 240 patients with GC who were aged >60 years. We compared past endoscopic images with newer ones, in which GC was diagnosed. IGC were classified into two categories: missed cancers and new cancers.

RESULTS

Of the 240 patients with GC, 32 had past endoscopic images that qualified for a precise review. A total of 14 cases involved new cancers, whereas 18 involved missed cancers. Most of the IGC were stage I for at least 2 years; however, a small subset was unresectable at >2 years after a negative endoscopy. Furthermore, the rate of endoscopic treatment was significantly higher for IGC compared with that for non-IGC.

CONCLUSIONS

In people aged >60 years, most IGC remain in an early stage for at least 2 years; however, at >2 years after a negative endoscopy, some are unresectable. These results suggest that most early-stage GC will not develop into advanced cancers within 2 years; thus, a 2-year interval might be within the permissible range for patients with negative endoscopy results for any lesions. Geriatr Gerontol Int 2018; 18: 997-1002.

Clinical efficacy of endoscopic ultrasonography for decision of treatment strategy of gastric cancer

BACKGROUND

Accurate preoperative tumor staging of gastric cancer is indispensable with expansion of indications for laparoscopic surgery and endoscopic resection. It is important to distinguish mucosal cancer (T1a) in smaller lesion and differentiate early gastric cancer (EGC) in larger lesion considering endoscopic resection indication and laparoscopic surgery indication. We evaluated the clinical outcomes of endoscopic ultrasonography (EUS) for the decision of treatment strategy of gastric cancer compared with pathological staging.

METHODS

The patients who underwent EUS and surgical or endoscopic resection for gastric cancer were retrospectively reviewed between September 2005 and February 2016. The depth of tumor invasion (T staging) by EUS was compared with the pathological staging after endoscopic or surgical resection.

RESULTS

A total of 6084 patients were finally analyzed. The accuracy rates for T1a and EGC were 75.0 and 89.4%, respectively. The overall accuracy of T staging by EUS was 66.3% when divided by T1a, T1b, and over T2. The accuracy of EUS prior to endoscopic resection was 75.1% in absolute indication and 73.1% in expanded criteria, respectively. The accuracy rates for T1a with lesion ≤ 2 cm in miniprobe EUS and EGC with lesion > 2 cm in conventional EUS were 84.6 and 83.2%, respectively. In multivariate analysis, presence of ulcer, large tumor size, and radial EUS were associated with overestimation, and small tumor size and miniprobe were associated with underestimation in T staging.

CONCLUSIONS

EUS showed the high accuracy of 84.6% for T1a in lesion ≤ 2 cm in miniprobe EUS and 83.2% for EGC in lesion > 2 cm in conventional EUS, respectively. EUS can be a complementary diagnostic method to determine endoscopic or surgical treatment modality.

Long-term outcome of endoscopic submucosal dissection is comparable to that of surgery for early gastric cancer: a propensity-matched analysis

BACKGROUND

Data concerning the long-term outcomes of endoscopic submucosal dissection (ESD) versus surgery for early gastric cancer (EGC) are limited. We aimed to compare the long-term outcomes of ESD and surgery for patients with EGC.

METHODS

Data were reviewed from patients treated by ESD or surgery for EGC in 2005-2010. The primary outcome was overall survival (OS). Secondary outcomes were disease-specific survival (DSS), disease-free survival (DFS), recurrence-free survival (RFS), treatment-related complications, and hospital stay duration.

RESULTS

Among 617 patients, 342 underwent ESD and 275 underwent surgery. The 5-year OS rates were similar between the ESD group and the surgery group (96.9% vs 98.1%, P = 0.581). In a propensity-score-matched analysis of 117 pairs, there were no significant differences in the OS rates (96.5% vs 99.1%, P = 0.125) and DSS rates (100% vs 99.1%, P = 0.317) between the ESD group and the surgery group. The ESD group had a significantly lower DFS rate (90.3% vs 98.0%, P = 0.002), a significantly lower RFS rate (95.1% vs 98.0%, P = 0.033), a significantly higher early complication rate (6.7% vs 1.5%, P < 0.001), a significantly lower late complication rate (0% vs 9.1%, P < 0.001), and a significantly shorter median hospital stay (3 days vs 10 days, P < 0.001) than the surgery group.

CONCLUSIONS

ESD and surgery have comparable OS rates in patients with EGC. ESD has benefits, including a lower late complication rate and shorter hospital stay. However, RFS and DFS rates might be lower after ESD than after surgery.

Linked color imaging (LCI), a novel image-enhanced endoscopy technology, emphasizes the color of early gastric cancer

BACKGROUND AND STUDY AIMS

 Linked color imaging (LCI) and blue laser imaging (BLI) are novel image-enhanced endoscopy technologies with strong, unique color enhancement. We investigated the efficacy of LCI and BLI-bright compared to conventional white light imaging (WLI) by measuring the color difference between early gastric cancer lesions and the surrounding mucosa.

PATIENTS AND METHODS

 Images of early gastric cancer scheduled for endoscopic submucosal dissection were captured by LCI, BLI-bright, and WLI under the same conditions. Color values of the lesion and surrounding mucosa were defined as the average of the color value in each region of interest. Color differences between the lesion and surrounding mucosa (ΔE) were examined in each mode. The color value was assessed using the CIE L*a*b* color space (CIE: Commission Internationale d'Eclairage).

RESULTS

 We collected images of 43 lesions from 42 patients. Average ΔE values with LCI, BLI-bright, and WLI were 11.02, 5.04, and 5.99, respectively. The ΔE was significantly higher with LCI than with WLI ( P  < 0.001). Limited to cases of small ΔE with WLI, the ΔE was approximately 3 times higher with LCI than with WLI (7.18 vs. 2.25). The ΔE with LCI was larger when the surrounding mucosa had severe intestinal metaplasia ( P  = 0.04). The average color value of a lesion and the surrounding mucosa differed. This value did not have a sufficient cut-off point between the lesion and surrounding mucosa to distinguish them, even with LCI.

CONCLUSION

 LCI had a larger ΔE than WLI. It may allow easy recognition and early detection of gastric cancer, even for inexperienced endoscopists.

Comparison of clinical outcomes after endoscopic submucosal dissection and surgery in the treatment of early gastric cancer: A single-institute study

The feasibility of expanding the indications for endoscopic submucosal dissection to treat early gastric cancer based on long-term outcomes has shown conflicting results. This study aimed to investigate whether outcomes or adverse events associated with endoscopic submucosal dissection are comparable to those of surgery for early gastric cancer that including the absolute and expanded indications.Data of 159 early gastric cancers from 153 patients treated with endoscopic submucosal dissection or surgery between January 2004 and October 2014 were reviewed retrospectively. Early gastric cancers fulfilled the absolute or expanded indications with differentiated type adenocarcinoma were included.The endoscopic submucosal dissection and surgery group showed no significant difference in the incidence of residual disease (P = .48), local recurrence (P = .46), and metachronous cancer (P = .22). Kaplan-Meier analysis showed no significant difference in 2-year (97.6% versus [vs] 92.4%; P = .45) and 5-year (95.8% vs 95.6%; P = .26) overall survival rate between 2 groups. There was also no significant difference in 2-year (100% vs 94.1%; P = .98) and 5-year (100% vs 98.4%; P = .89) disease-free survival rate. Early and late adverse events also showed no significant differences.For the treatment of early gastric cancer fulfilled absolute and expanded indications, endoscopic submucosal dissection is not inferior modality regarding the clinical outcomes and safety, compared with surgery.

Effectiveness of Gastric Cancer Screening on Gastric Cancer Incidence and Mortality in a Community-Based Prospective Cohort

Purpose

This study was performed to investigate the effectiveness of gastric cancer (GC) screening methods in a community-based prospective cohort of the Korean Multi-center Cancer Cohort (KMCC) with over a 10-year follow-up.

Materials and Methods

A total 10,909 and 4,773 subjects from the KMCC with information on gastroendoscopy (GE) and upper gastrointestinal series (UGIS) were included in this study. Cox proportional hazard model adjusted for age, sex, Helicobacter pylori infection, cigarette smoking, and alcohol drinking was used to estimate the hazard ratios (HRs) and 95% confidence interval (CI).

Results

The GE screened subjects had almost half the risk of GC-specific death than that of unscreened subjects (HR, 0.58; 95% CI, 0.36 to 0.94). Among the GC patients, GE screenees had a 2.24-fold higher survival rate than that of the non-screenees (95% CI, 1.61 to 3.11). In particular, GE screenees who underwent two or more screening episodes had a higher survival rate than that of the non-screenees (HR, 13.11; 95% CI, 7.38 to 23.30). The effectiveness of GE screening on reduced GC mortality and increased survival rate of GC patients was better in elderly subjects (≥ 65 years old) (HR, 0.47; 95% CI, 0.24 to 0.95 and HR, 8.84; 95% CI, 3.63 to 21.57, respectively) than that in younger subjects (< 65 years old) (HR, 0.66; 95% CI, 0.34 to 1.29 and HR, 1.83; 95% CI, 1.24 to 2.68, respectively). In contrast, UGIS screening had no significant relation to GC mortality and survival.

Conclusion

The findings of this study suggest that a decreased GC-specific mortality and improved survival rate in GC patients can be achieved through GE screening.

Gastric adenocarcinoma

Gastric cancers, with gastric adenocarcinoma (GAC) as the most common histological type, impose a considerable global health burden. Although the screening strategies for early detection have been shown to be successful in Japan and South Korea, they are either not implemented or not feasible in most of the world, leading to late diagnosis in most patients. Helicobacter pylori infection contributes to the development of many endemic GACs, and pre-emptive eradication or early treatment of this bacterial infection might provide effective primary prevention. GACs are phenotypically and genotypically heterogeneous. Localized (clinical stage I) GAC is best treated either endoscopically or with limited surgical resection, but clinical stage II or stage III tumours require multidisciplinary adjunctive approaches in addition to surgery. Although GAC is highly treatable in its early stages, advanced (clinical stage IV) GAC has a median survival of just ∼9-10 months. However, detailed molecular and immune profiling of GAC is yielding promise; early studies with immune checkpoint inhibitors suggest that GAC is amenable to immune modulation. Molecular studies have yielded a vast quantity of new information for potential exploitation. Nevertheless, advances against GACs have lagged compared with other tumours of similar incidence, and more research is necessary to overcome the obstacles to prolong survival.

Therapeutic outcomes of endoscopic submucosal dissection for early gastric cancer: single-center study

OBJECTIVES

Endoscopic submucosal dissection (ESD) has been widely accepted for selected patients with early gastric cancer (EGC). The aim of this study was to assess the therapeutic outcomes after ESD according to the pathological extent.

PATIENTS AND METHODS

From January 2005 to December 2014, a total of 599 patients with 611 lesions were enrolled in this study. The tumors were categorized according to pathological results on the basis of absolute criteria (AC), expanded criteria (EC), EC with undifferentiated histology [(EC-U), mucosal cancer, ulcer (-), ≤20 mm], or beyond EC (BEC). The therapeutic outcomes among the four groups were analyzed retrospectively.

RESULTS

The number of patients in the AC, EC, EC-U, and BEC groups was 447, 91, 19, and 54. The complete resection rates of EGC were 97.8, 84.6, 94.4, and 45.5% (P=0.001) and en bloc resection rates in the AC, EC, EC-U, and BEC groups were 99.1, 98.9, 100, and 98.1% (P=0.833), respectively. The 5-year disease-free survival rate in the AC, EC, EC-U, and BEC groups was 90.6, 88.7, 75.0, and 83.3% (P=0.394). In multivariate analysis, undifferentiated histology (P=0.001) and tumor size (>30 mm, P=0.017) were risk factors related to local recurrence.

CONCLUSION

The efficacy of ESD for EGCs in EC is almost equal to that in AC when complete resection was achieved. However, the indication for ESD should be decided conservatively because the complete resection rate of EGC in the EC group was significantly lower than that in the AC group. Undifferentiated histology and tumor size over 30 mm were risk factors related to local recurrence.

Does the interval of screening endoscopy affect survival in gastric cancer patients?: A cross-sectional study

Gastric cancer remains the second most common cancer in Korea; however, its mortality has decreased due to earlier diagnosis. In Korea, screening endoscopy has been performed nationwide since 1999. The aim of this study was to elucidate the benefit of screening endoscopy on actual survival in gastric cancer patients and to determine the optimal interval of screening endoscopy.We analyzed 1651 patients diagnosed with gastric adenocarcinoma who underwent surgical treatment between June 2008 and December 2014. Patients were divided into 4 groups according to the interval of screening endoscopy prior to their gastric cancer diagnosis. (Group I = within 1 year, Group II = >1 but <2 years, Group III = more than 2 years, Group IV = no prior endoscopic examination). Patient demographics, clinicopathologic characteristics, and postoperative surgical outcomes including overall survival were compared.The 5-year gastric cancer-specific survival rates of groups I and II were significantly higher than groups III and IV (90.9% vs 85.4%, P = 0.002, respectively). Multivariate analysis showed that screening interval was an independent factor for the diagnosis of advanced gastric cancer. The risk of advanced gastric cancer decreased in group I (odds ratio: 0.515, 95% confidence interval [CI] 0.369-0.719; P < 0.001) and group II (odds ratio: 0.678, 95% CI 0.517-0.889, P = 0.005).Screening endoscopy was helpful in increasing the survival of gastric cancer patients. A 2-year endoscopic screening interval is suitable to detect early-stage gastric cancer.

Gastric cancer and family history

Gastric cancer is associated with high morbidity and mortality rates worldwide. Identifying individuals at high risk is important for surveillance and prevention of gastric cancer. Having first-degree relatives diagnosed with gastric cancer is a strong and consistent risk factor for gastric cancer, but the pathogenic mechanisms behind this familial aggregation are unclear. Against this background, we reviewed the risk factors for gastric cancer in those with a first-degree relative with gastric cancer, and the possible causes for familial clustering of gastric cancer including bacterial factors, inherited genetic susceptibility, environmental factors or a combination thereof. Among individuals with a family history, current or past Helicobacter pylori infection, having two or more first-degree affected relatives or female gender was associated with an increased risk of developing gastric cancer. To date, no specific single nucleotide polymorphism has been shown to be associated with familial clustering of gastric cancer. H. pylori eradication is the most important strategy for preventing gastric cancer in first-degree relatives of gastric cancer patients, particularly those in their 20s and 30s. Early H. pylori eradication could prevent the progression to intestinal metaplasia and reduce the synergistic effect on gastric carcinogenesis in individuals with both H. pylori infection and a family history. Endoscopic surveillance is also expected to benefit individuals with a family history. Further large-scale, prospective studies are warranted to evaluate the cost-effectiveness and optimal time point for endoscopy in this population. Moreover, genome-wide association studies that incorporate environmental and dietary factors on a 'big data' basis will increase our understanding of the pathogenesis of gastric cancer.

Effectiveness of systematic alphanumeric coded endoscopy for diagnosis of gastric intraepithelial neoplasia in a low socioeconomic population

Background and study aims: In the Western world, gastric cancer (GC) usually presents at an advanced stage, carrying a high mortality rate. Studies have reported that 14 % to 26 % of GCs are missed at endoscopy up to 3 years before diagnosis. Systematic Alphanumeric Coded Endoscopy (SACE) has been proposed to improve quality of esophagogastroduodenoscopy (EGD) by facilitating a complete examination of the upper gastrointestinal tract. This prospective cross-sectional study was designed to determine the frequency of gastric intraepithelial neoplasia (GIN) by using the SACE approach in cohort of patients from low socioeconomic level. It also used non-targeted biopsies to evaluate the frequency of premalignant conditions. Patients and methods: A total of 601 consecutive asymptomatic or dyspeptic patients were enrolled between January 2013 and November 2014 at the Huacho regional hospital in Peru. The SACE method proposed by Emura et al, which divides the stomach into 5 regions and 21 areas, was routinely used for diagnosis. Biopsy samples were obtained from any endoscopically detected focal lesion. To evaluate gastric premalignant conditions, 4 non-targeted biopsies were taken. Results: A total of 573 patients were analyzed. The mean age was 57 years, and the female:male ratio was 1.9 : 1. In all cases, complete photo-documentation of the 21 gastric areas was achieved. The overall rate of detection of GIN was 2.8 %. Low-grade displasia, high-grade dysplasia, and adenocarcinoma were found in 13 (2.3 %), 2 (0.3 %), and 1 (0.2 %) of the patients, respectively. The prevalence of at least 1 premalignant condition was 31 %, and helicobacter pylori infection was found in 57 % of patients. Conclusions: Using the SACE approach and with proper training, we have reported herein a high frequency of GIN in patients from a low socioeconomic status. Gastric cancer detection can be improved in a Western endoscopy setting when SACE, as a screening method, is performed by a trained endoscopist.

Screening and surveillance for gastric cancer in the United States: Is it needed?

BACKGROUND AND AIMS

Although the incidence of gastric cancer in the United States is relatively low, the incidence of gastric cancer is higher than for esophageal cancer, for which clear guidelines for screening and surveillance exist. With the increasing availability of endoscopic therapy, such as endoscopic submucosal dissection, for treating advanced dysplasia and early gastric cancer, establishing guidelines for screening and surveillance of patients who are at high risk of developing gastric cancer has the potential to diagnose and treat gastric cancer at an earlier stage and improve mortality from gastric cancer. The aims of this article were to review the data regarding the risk factors for developing gastric cancer, methods for gastric cancer screening, and results of national screening programs.

METHODS

A review of the existing literature related to the aims was performed.

RESULTS

Risk factors for gastric cancer that were identified include race/ethnicity (East Asian, Russian, or South American), first-degree relative diagnosed with gastric cancer, positive Helicobacter pylori status, and presence of atrophic gastritis or intestinal metaplasia. Endoscopy has the highest rate of detecting gastric cancer compared with other gastric cancer screening methods. The national screening program in Japan has demonstrated a mortality reduction from gastric cancer based on cohort data.

CONCLUSIONS

Gastric cancer screening with endoscopy should be considered in individuals who are immigrants from regions associated with a high risk of gastric cancer (East Asia, Russia, or South America) or who have a family history of gastric cancer. Those with findings of atrophic gastritis or intestinal metaplasia on screening endoscopy should undergo surveillance endoscopy every 1 to 2 years. Large prospective multicenter studies are needed to further identify additional risk factors for developing gastric cancer and to assess whether gastric cancer screening programs for high-risk populations in the United States would result in improved mortality.

Risk factors for local recurrence after en bloc endoscopic submucosal dissection for early gastric cancer

AIM: To investigate factors related to recurrence following en bloc resection using endoscopic submucosal dissection (ESD) in patients with early gastric cancer (EGC).

METHODS: A total of 1121 patients (1215 lesions) who had undergone ESD for gastric neoplasia between April 2003 and May 2010 were retrospectively reviewed. Data from 401 patients (415 lesions) were analyzed, following the exclusion of those who underwent piecemeal resection, with deep resection margin invasion or lateral margin infiltration, and diagnosed with benign lesions.

RESULTS: Local recurrence after en bloc ESD was found in 36 cases (8.7%). Unclear resection margins, long procedure times, and narrow safety margins were identified as risk factors for recurrence. Lesions located in the upper third of the stomach showed a higher rate of recurrence than those located in the lower third of the stomach (OR = 2.9, P = 0.03). The probability of no recurrence for up to 24 mo was 79.9% in those with a safety resection margin ≤ 1 mm and 89.5% in those with a margin > 1 mm (log-rank test, P = 0.03).

CONCLUSION: Even in cases in which en bloc ESD is performed for EGC, local recurrence still occurs. To reduce local recurrences, more careful assessment will be needed prior to the implementation of ESD in cases in which the tumor is located in the upper third of the stomach. In addition, clear identification of tumor boundaries as well as the securing of sufficient safety resection margins will be important.

Effect of Helicobacter pylori infection and its eradication on the fate of gastric polyps

OBJECTIVES

Western guidelines recommend Helicobacter pylori eradication in H. pylori-associated gastric polyps, but Korean medical insurance does not approve its eradication. The aim of this study is to evaluate the effect of H. pylori eradication on gastric polyps.

METHODS

Participants in a large screening cohort underwent baseline and follow-up esophagogastroduodenoscopy and H. pylori testing. The association between gastric polyps and H. pylori was estimated using odds ratios (ORs) adjusted for confounding factors and 95% confidence intervals (CIs). The effect of H. pylori eradication on the fate of polyps was also evaluated.

RESULTS

The screening cohort included 7603 participants (605 gastric polyps: 529 hyperplastic polyps, 63 fundic gland polyps, and 13 adenomas). H. pylori infection showed a positive association with hyperplastic polyps (OR 2.01; 95% CI 1.66-2.41), but was inversely related to fundic gland polyps (OR 0.05; 95% CI 0.02-0.17). Removed polyps by biopsy or endoscopic resection or tiny polyps less than 3 mm at baseline and positive conversion of H. pylori at follow-up were excluded. A total of 7060 persons were finally included to evaluate the effect of H. pylori eradication on the gastric polyp. Successful H. pylori eradication (OR 0.52; 95% CI 0.35-0.77) and persistent H. pylori-negative status (OR 0.59; 95% CI 0.46-0.76) reduced the risk of hyperplastic polyps compared with the persistent H. pylori-positive group. Successful H. pylori eradication markedly induced the disappearance of hyperplastic polyps compared with the persistent H. pylori-positive group (85.0 vs. 29.0%, P=0.001).

CONCLUSION

H. pylori infection increased the risk of hyperplastic polyps in both cross-sectional and longitudinal settings, and its eradication induced regression of hyperplastic polyps.

The Influence of Gastric Cancer Screening on the Stage at Diagnosis and Survival: A Meta-Analysis of Comparative Studies in the Far East

Gastric cancer is the fifth most common cancer and the second most common cause of cancer-related death worldwide. The aim of this review was to evaluate the effect of gastric cancer screening on the stage at diagnosis and survival from disease. A systematic review of the literature between January 1995 and December 2014 was performed. Studies that compared screened versus nonscreened populations for the diagnosis of gastric cancer and included the stage at diagnosis were analyzed. The QUADAS-2 and the ROBANS tools were used to assess the quality of the studies. A total of 11 studies from the Far East comprising 4039 participants in the screened and 6635 in the nonscreened groups were included. Screening was associated with a significant increase in the detection of early gastric cancer (EGC) [pooled odds ratio (POR)=3.90; 95% confidence interval (CI), 3.01-5.06; P<0.0001] and reduction in the incidence of advanced gastric cancer (POR=0.27; 95% CI, 0.20-0.35; P<0.0001). Furthermore, screening improved the 5-year survival significantly (hazard ratio=0.56; 95% CI, 0.48-0.66; P<0.0001). About 73% of the screened patients were found to have EGC compared with 43% of the nonscreened patients. About 8% of the screened patients were found to have advanced gastric cancer compared with 54% of the nonscreened patients. Screening for gastric cancer is useful in detecting asymptomatic patients with EGC in high-prevalence areas. This in turn increases the number of treatable cancers and improves the 5-year survival. There is a need for the development and the validation of alternative risk-stratification tools in low-incidence areas to allow for similar benefits.

Long-Term Outcome of Endoscopic Resection vs. Surgery for Early Gastric Cancer: A Non-inferiority-Matched Cohort Study

OBJECTIVES

Few studies have compared the long-term outcomes of endoscopic resection and surgery. The aim of this study was to compare the long-term outcomes of endoscopic resection with those of surgery for early gastric cancer (EGC).

METHODS

We reviewed prospectively collected data of patients who had undergone endoscopic resection (1,290 patients) or surgery (1,273 patients) for EGC. To reduce the effect of selection bias, we performed a propensity score-matching analysis between the two groups. The primary outcome was overall survival (OS). The secondary outcomes were disease-specific survival, disease-free survival (DFS), recurrence-free survival (RFS), occurrence of metachronous gastric cancer, treatment-related complications, length of hospital stay, and 30-day outcomes. The study was designed as a non-inferiority study and tested in an intention-to-treat analysis.

RESULTS

In a propensity-matched analysis of 611 pairs, the 10-year OS proportion was 96.7% in the endoscopic resection group and 94.9% in the surgery group (P=0.120) (risk difference -1.8%, 95% confidence interval (CI) -4.04-0.44, Pnon-inferiority=0.014), which met the non-inferiority criterion. In contrast, the 10-year RFS proportion was 93.5% in the endoscopic resection group and 98.2% in the surgery group (P<0.001) (risk difference 4.7%, 95% CI 2.50-6.97, Pnon-inferiority=0.820), which did not meet the non-inferiority criterion, mainly because of metachronous recurrence in the endoscopic resection group. The rate of early complications was higher in the endoscopic resection group than in the surgery group (9.0 vs. 6.6%, P=0.024), whereas the rate of late complications was higher in the surgery group than in the endoscopic resection group (0.5 vs. 2.9%, P<0.001). In the multiple Cox regression analysis, patient's age, the comorbidity index, the performance index, sex, tumor morphology, and depth of invasion were predictors of OS in patients with EGC.

CONCLUSIONS

Endoscopic resection might not be inferior to surgery with respect to OS in patients with EGC lesions that meet the absolute or expanded criteria. However, DFS, RFS, and metachronous RFS might be lower after endoscopic resection than after surgery.

Clinicopathologic characteristics of interval gastric cancer in Korea

Background/Aims

Interval gastric cancer (IGC) is defined as cancer that is diagnosed between the time of screening and postscreening esophagogastroduodenoscopy (EGD). Unfortunately, little is known about the characteristics of IGC in Korea, a country with a high incidence of gastric cancer. The aim of this study was to evaluate the clinicopathologic characteristics of IGCs in Korea.

Methods

From January 2006 to July 2011, a total of 81,762 subjects underwent screening EGD at Yonsei University Health Promotion Center, Seoul, Korea. We defined missed cancer as cancer diagnosed within 1 year of screening EGD and latent cancer as cancer diagnosed more than 1 year after EGD.

Results

A total of 16 IGC patients (17 lesions; three missed cancers and 14 latent cancers) were identified, with a mean age of 60.68 years and a mean interval time of 19.64 months. IGCs tended to be undifferentiated (12/17, 70.6%), located in the lower body of the stomach (12/17, 70.6%) and exhibited flat/depressed endoscopic morphology (11/17, 64.7%). The patients with missed cancer were generally younger than the patients with latent cancer (51.3 years vs 62.8 years, p=0.037), and the patients with undifferentiated cancer were significantly younger than those with differentiated cancer (57.0 years vs 68.8 years, p=0.008).

Conclusions

IGCs tended to be undifferentiated, located in the lower body of the stomach, and exhibited flat/depressed endoscopic morphology.

Diagnosis and management of high risk group for gastric cancer

Gastric cancer is associated with high morbidity and mortality worldwide. To reduce the socioeconomic burden related to gastric cancer, it is very important to identify and manage high risk group for gastric cancer. In this review, we describe the general risk factors for gastric cancer and define high risk group for gastric cancer. We discuss strategies for the effective management of patients for the prevention and early detection of gastric cancer. Atrophic gastritis (AG) and intestinal metaplasia (IM) are the most significant risk factors for gastric cancer. Therefore, the accurate selection of individuals with AG and IM may be a key strategy for the prevention and/or early detection of gastric cancer. Although endoscopic evaluation using enhanced technologies such as narrow band imaging-magnification, the serum pepsinogen test, Helicobacter pylori serology, and trefoil factor 3 have been evaluated, a gold standard method to accurately select individuals with AG and IM has not emerged. In terms of managing patients at high risk of gastric cancer, it remains uncertain whether H. pylori eradication reverses and/or prevents the progression of AG and IM. Although endoscopic surveillance in high risk patients is expected to be beneficial, further prospective studies in large populations are needed to determine the optimal surveillance interval.

Impact of periodic endoscopy on incidentally diagnosed gastric gastrointestinal stromal tumors: findings in surgically resected and confirmed lesions

BACKGROUND

Although gastric gastrointestinal stromal tumors (GISTs) are usually identified by endoscopic examinations, the diagnostic value of endoscopy has not been fully evaluated. We assessed the diagnostic performance of endoscopy for gastric GISTs according to lesion characteristics. Furthermore, the benefits of periodic endoscopy prior to diagnosis of gastric GISTs were evaluated.

METHODS

We reviewed patients who underwent surgery for gastric GISTs at Severance Hospital, Seoul, Korea, between January 2008 and April 2014. In addition, we administered a questionnaire to determine the usage of periodic endoscopic inspection and the period from the penultimate endoscopy to the diagnosis.

RESULTS

Of 174 included patients, 109 (62.4 %) showed intraluminally growing GISTs and 65 (37.4 %) showed extraluminally growing GISTs. The proportions of lesions that were initially diagnosed via endoscopy were 99.1 % for intraluminally growing GISTs and 49.2 % for extraluminally growing GISTs (P < 0.001). In patients with intraluminally growing GISTs, patients who had undergone endoscopy within 3 years prior to the diagnosis showed smaller tumor sizes (P = 0.015) and fewer tumors with ulceration (7.1 vs. 28.4 %, P = 0.021). The proportion of GISTs with a high mitotic index did not differ according to the usage of periodic endoscopy (P = 0.639). In contrast, lesion characteristics of the extraluminally growing GISTs did not differ according to whether an endoscopy was performed within 3 years prior to the diagnosis.

CONCLUSIONS

Endoscopic examinations had a limited role in the diagnosis of extraluminally growing GISTs. However, periodic endoscopy was associated with relatively earlier detection of growth in intraluminal gastric GISTs.

Improving the Endoscopic Detection Rate in Patients with Early Gastric Cancer

Endoscopists should ideally possess both sufficient knowledge of the endoscopic gastrointestinal disease findings and an appropriate attitude. Before performing endoscopy, the endoscopist must identify several risk factors of gastric cancer, including the patient's age, comorbidities, and drug history, a family history of gastric cancer, previous endoscopic findings of atrophic gastritis or intestinal metaplasia, and a history of previous endoscopic treatments. During endoscopic examination, the macroscopic appearance is very important for the diagnosis of early gastric cancer; therefore, the endoscopist should have a consistent and organized endoscope processing technique and the ability to comprehensively investigate the entire stomach, even blind spots.

Prediction Model for Gastric Cancer Incidence in Korean Population

BACKGROUND

Predicting high risk groups for gastric cancer and motivating these groups to receive regular checkups is required for the early detection of gastric cancer. The aim of this study is was to develop a prediction model for gastric cancer incidence based on a large population-based cohort in Korea.

METHOD

Based on the National Health Insurance Corporation data, we analyzed 10 major risk factors for gastric cancer. The Cox proportional hazards model was used to develop gender specific prediction models for gastric cancer development, and the performance of the developed model in terms of discrimination and calibration was also validated using an independent cohort. Discrimination ability was evaluated using Harrell's C-statistics, and the calibration was evaluated using a calibration plot and slope.

RESULTS

During a median of 11.4 years of follow-up, 19,465 (1.4%) and 5,579 (0.7%) newly developed gastric cancer cases were observed among 1,372,424 men and 804,077 women, respectively. The prediction models included age, BMI, family history, meal regularity, salt preference, alcohol consumption, smoking and physical activity for men, and age, BMI, family history, salt preference, alcohol consumption, and smoking for women. This prediction model showed good accuracy and predictability in both the developing and validation cohorts (C-statistics: 0.764 for men, 0.706 for women).

CONCLUSIONS

In this study, a prediction model for gastric cancer incidence was developed that displayed a good performance.

Age and sex interactions in gastric cancer incidence and mortality trends in Korea

BACKGROUND

The incidence and mortality of gastric cancer have declined rapidly over the past few decades, but reverse trends in the young generation's differential between sexes in some races have been reported in recent years. To investigate whether this divergent trend can be observed in Korea, a country with the highest incidence in the world, age- and sex-specific incidence and mortality trends were evaluated.

METHODS

Gastric cancer incidence data for the years 1999-2010 and mortality data for the years 1983-2012 were obtained from the Korea Central Cancer Registry and National Statistical Office. Annual percentage changes were calculated by age group (20-39, 40-54, 55-69, 70-79) using Joinpoint regression analysis. Furthermore, age-period-cohort analysis was evaluated.

RESULTS

Overall age-standardized gastric cancer incidence in adults aged between 20 and 79 was declining at a nonsignificant average annual percentage change (AAPC) of -0.2 % in males and -0.4 % in females in Korea during 1999-2010. Mortality was steeper at a significant rate of -4.3 and -5.9 % in males and females, respectively. However, age-specific analysis revealed a flat (males 0.2 %, 95 % CI -0.5-0.6) or increasing incidence trend (females 1.7 %, 95 % CI 0.9-2.5) in the 40-54 age group. APC analysis confirmed the decreasing incidence and mortality trend mainly by the cohort effect.

CONCLUSIONS

The differential pattern between males and females in different age groups suggests a possible effect of detection by screening practice or a signal of the change in epidemiological factors in the incidence and mortality of gastric cancer that warrants further studies.

Risk factors of developing interval early gastric cancer after negative endoscopy

BACKGROUND

New or missed gastric cancer rates after negative endoscopy are high. However, the clinicopathologic characteristics of missed or interval early gastric cancer (EGC) are not well known. The aim of this study was to evaluate clinicopathologic and endoscopic characteristics of missed or interval EGC after negative endoscopy.

METHODS

We retrospectively analyzed 1,055 patients with EGC confirmed by endoscopic resection or surgery between June 2006 and July 2013. Referred patients with diagnosed or suspected gastric neoplasms were excluded (n = 771). Interval EGC was defined as gastric cancer diagnosed within 2 years of negative endoscopy. Clinicopathologic characteristics of patients with initially detected and interval EGC and risk factors for interval EGC were investigated.

RESULTS

Of 284 patients, 52 had interval EGC (18.3 %; mean age 65.4 years; average interval between diagnosis and previous endoscopy, 12.6 months). Tumors were significantly smaller (1.3 vs. 1.8 cm, P < 0.001), and the incidence of metaplasia was significantly higher (90.4 vs. 65.9 %, P < 0.001) for interval EGC than for initially detected EGC. And no symptoms (50 vs. 17.7 %, P < 0.001) were significantly associated with interval EGC. However, tumor location, differentiation, gross morphology, and Helicobacter pylori infection status did not differ significantly.

CONCLUSIONS

Subtle mucosal lesions with surrounding intestinal metaplasia were associated with interval EGC. Careful endoscopic screening for patients with intestinal metaplasia at short-term interval would be beneficial for decreasing interval EGC rates.